1. Field of the Invention
This invention relates to apparatus and method for selectively blocking the reproduction of a video title, based on a password entered by a user, in a reproduction apparatus for playback of an optical disk on which several data blocks for specific sections or parts of a single title are recorded, such data blocks differing from each other in contents and rating level.
2. Description of the Related Art
FIG. 1 depicts a functional block diagram of an optical disk reproduction apparatus to which a preferred embodiment of the present invention is applied, comprising an optical pickup 2 for reading out information recorded in an optical disk 1 by using a light beam irradiated by an LED; a spindle motor 3 for rotating the optical disk; a sled motor 4 for moving the optical pickup in the radial direction of the optical disk; a driving unit 8 for driving the sled motor and the spindle motor; an radio-frequency (RF) processing unit 5 for filtering and shaping the signal picked up by the optical pickup into binary signals; a sync-clock generator 6 for synchronizing its clock with the binary signals; a servo unit 7 for servo-controlling the driving unit; a digital signal processor 9 for processing the binary signals on the basis of the synchronized clock and then extracting an MPEG-encoded moving picture data; an MPEG decoder 10 for decoding the MPEG-encoded moving picture into audio and video signals; a memory 13 for storing a password, or identification number (xe2x80x9cPINxe2x80x9d) entered by a user; a microcomputer (microcomputer) 11 for controlling reproduction operation based on a result of comparison between the stored password and the password entered; a keypad 14 for inputting a command of a user; and on screen display (OSD) unit for outputting the comparison result on a screen of the reproduction apparatus.
For such an optical disk reproduction apparatus, once a user enters a password or PIN through the keypad 14, the password is stored in the memory 13 under control of the microcomputer 11. After that, if a user requests the reproduction of an optical disk, the prescribed message like xe2x80x9cEnter passwordxe2x80x9d is retrieved from an OSD character data set stored in the memory 13 and is then applied to the OSD unit 12 for display.
Then, the OSD unit generates character image signal corresponding to the message to ask the user to enter a password. Once a password is entered, the microcomputer 11 compares the password stored in the memory 13 with a password entered.
If it is determined that they are identical, the microcomputer 11 controls the servo unit 7 and driving unit 8 so that the optical pickup 2 is moved to a prescribed track on the optical disk 1 and starts to read out recorded data thereon. The read-out data is decoded into moving picture data by the RF processing unit 5 and digital signal processing unit 9. The moving picture data is then decoded into audio and video signals by the MPEG decoder 10.
On the other hand, if they are not matched, the microcomputer 11 retrieves a message like invalid password xe2x80x9cout of the OSD character data set and then sends it to the OSD unit 12. The OSD unit 12, in turn, generates and outputs the corresponding character image signal so that the user is asked to re-enter a password.
Meanwhile, an optical disk 1 is generally composed of a video data storage region for storing at least one video data sequence, wherein each video data sequence has a plurality of video segments of a reproduction period, a plurality of sub-pictures and a plurality of control procedures, and a management information storage region which stores management information such as video management information (hereinafter, VMGI) or video title setting information (hereinafter, VTSI). A program chain (hereinafter, PGC) addressing video data block, that is a list of video objects (VOBs), which specifies their reproduction order, is provided in such an optical disk. By setting the PGC sequence, it is possible that video objects are organized such that reproduction of several video data blocks are provided with different contents, as shown in FIG. 2.
Video titles or video/audio contents on them are, generally, classified into three ratings: xe2x80x9cadultxe2x80x9d, xe2x80x9cparental guidancexe2x80x9d (hereinafter PG), and xe2x80x9ckids safexe2x80x9d ratings in terms of their contents.
FIG. 3 shows a flowchart of a password-based conventional art method of blocking offensive or inappropriate material from being displayed in a reproduction apparatus. For the conventional art method, the reproduction of the inappropriate material is performed only when a password entered matches the stored password in the apparatus. If they are mismatched, a message indicating that the password entered is not correct is displayed on a screen of the apparatus, thereby the reproduction being not allowed until a correct password is entered by a user.
It is common that the conventional art method asks a user to enter the correct password repeatedly if the password entered is not correct. In other words, repetitive guessing of the correct password is not prohibited and thus the correct password can, by chance, be figured out. Therefore, a new method of restricting chances of re-entering a password is needed to effectively prevent video data with offensive or inappropriate material from being reproduced by children or teenagers.
The invention, in part, provides a method of selectively blocking reproduction of a video title by restricting chances of re-entering a password when a password entered by a user is not correct. In addition, when the password is not entered correctly, no warning message is displayed or the same message is displayed as in the case of password matching.
The invention provides, in part, an apparatus for and corresponding method of selectively blocking reproduction of a part of a video title, the method comprising the steps of checking whether a password entered is correct or not for a chosen rating level; and reproducing, for a part of said video title having two or more alternate data blocks of different rating levels, respectively, one of said data blocks that is of a different rating level than a rating level corresponding to the password when the password entered is incorrect.
The invention also provides, in part, an apparatus for and corresponding method of selectively blocking reproduction of a part of a video title according to the present invention comprises the steps of checking whether a password entered is correct or not for a chosen rating level; and reproducing contents of a rating level that are different than a chosen rating level for part of the video title whenever the part contains blocks corresponding to two or more rating levels, respectively, when the password entered is incorrect.
According to methods embodying the present invention, a user is asked to enter a password to watch a video title. Once a password is entered, a comparison is then made to check whether or not the password entered is correct. If the password is correct, the contents of the video title corresponding to a rating level that the user chose starts to be reproduced. Otherwise, predetermined contents provided in the video title, for example, a xe2x80x9ckids safexe2x80x9d version, are reproduced without giving a chance to re-enter a password.
The invention also provides, in part, an apparatus for and corresponding a method of selectively blocking reproduction of a part of a video title, wherein a user must enter a password to be able to view scenes corresponding to a chosen rating level. Such a method comprises: checking whether the password is correct or incorrect for the chosen rating level; and not displaying a data block having the chosen/desired rating level for that particular part of the video title when the password is entered incorrect.
The foregoing and other objectives of the present invention will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.